PROVIDENCIALES, Turks & Caicos Islands - Tropical Storm Bertha was moving over the Turks & Caicos Islands and the southeastern Bahamas on Sunday after emerging from the Dominican Republic, where overflowing rivers led to the temporary evacuation of dozens of families.

As the storm system swirled over the British Caribbean dependency of the Turks and Caicos, its maximum sustained winds were measured at about 45 mph, but some strengthening was expected over the next two days. Bertha was moving northwest at 18 mph with tropical storm force winds extending outward up to 160 miles.

The U.S. National Hurricane Center in Miami said the storm was likely to curve to the northeast and move parallel to the U.S. eastern seaboard without hitting the mainland. It was also expected to steer clear of the mid-Atlantic British territory of Bermuda later in the week. Officials described the storm thus far as largely disorganized, reports CBS Miami.

Turks & Caicos residents wary of a possible blow from Bertha pulled boats ashore or moored them at marinas in the tourism-dependent archipelago that has little natural protection from powerful storm surges. Tourism Director Ralph Higgs said hoteliers were "taking the threat of the storm seriously."

NOAA

Some American vacationers on the resort-lined Grace Bay strip on the chain's main island of Providenciales said they were weren't worried about the approaching tropical system.

"I plan to stay here and ride it out," Dave Pescan of Cleveland, Ohio, said as nearby work crews cleared storm drains and trimmed branches of trees growing near buildings.

On the southernmost Bahamian island of Inagua, residents were advised Saturday to make final preparations to protect their properties. But many islanders were instead focused on completing a popular sailing regatta before the storm ruined the fun.

"We're all partying because it's homecoming regatta. Honestly, no one's focusing on the weather," said Inagua resident Shakera Forbes.

On the Bahamas' most populous island of New Providence, resident Margaret Johnson said she was monitoring the progress of Bertha as it tracked toward the southeast part of the sprawling archipelago of roughly 700 islands, islets and cays off Florida's east coast.

"I'm watching and waiting," Johnson said from the capital of Nassau.

But on Sunday, the islands' government discontinued the tropical storm watch for the middle of the chain as the storm was expected to pass to the east of the central Bahamas late Sunday.

In the Dominican Republic, the government discontinued a tropical storm warning for the eastern Dominican Republic early Sunday. But the director of the emergency operations center, Juan Manuel Mendez, said residents needed to remain alert because heavy rain was still falling in parts of the country's east.

Due to choppy, white-crested waves, officials warned tourism businesses to cancel any water activities and prohibited fishing boats from taking to the water on much of the Caribbean nation's drenched east coast.

The storm passed just southwest of Puerto Rico on Saturday, dropping between 3 to 5 inches of rain, with isolated amounts of up to 8 inches.

Authorities on the U.S. Caribbean island said Sunday that nearly 29,000 households were without electricity. Most of the power outages occurred in the central mountainous region following more than 1,200 lightning strikes that occurred in the area during afternoon hours alone.

Some 220 people arrived at several government shelters in Puerto Rico's southeast region, the majority of them international athletes participating in a youth baseball tournament.

Ingrid Vila, gubernatorial chief of staff, said Puerto Rico's main international airport remained open but that several flights had been cancelled.

Downed trees limbs also were reported across St. Croix in the U.S. Virgin Islands, where a coastal buoy south of St. Thomas recorded wind gusts of 72 mph.

Bertha earlier left 150,000 homes without power on the French Caribbean island of Martinique and hundreds of people without power along Dominica's eastern region.